1. Field of the Invention
The invention relates to footwear, in particular a sports boot, and more particularly a boot that can be used in fields such as cross-country skiing, ski touring or telemark skiing, snowshoeing, roller skating or ice skating, or the like.
2. Background Information
A boot can include a low upper or a high upper, or even a mid-upper, and can be relatively flexible or, conversely, more rigid. In any case, the boot is provided with an outer sole assembly, which is adapted to connect the upper to the ground or to a sports apparatus, such as a ski or other gliding or rolling device.
The outer sole assembly is an element that extends lengthwise from a rear end to a front end, widthwise between a lateral side and a medial side, and heightwise between a free surface, adapted to contact the ground or the sports apparatus, and a connection surface, adapted to be affixed to the upper.
In a known manner, the outer sole assembly sometimes has a longitudinal groove that opens out in the area of the free surface. On occasion, the outer sole assembly has a plurality of longitudinal grooves. This is the case, for example, in the field of cross-country skiing, in which at least one groove is adapted to cooperate with a longitudinal guide rib of a guiding device. The rib is associated with a ski, directly or indirectly. Due the cooperation of each groove of the sole assembly with the associated rib, the boot is guided during the rolling movement of the foot during strides and is maintained transversely, in particular when the foot is in support over the entire length of the sole assembly. This arrangement enables precise steering of the ski, in spite of the boot being retained thereon so that the heel of the boot can be alternately raised and lowered.
This principle is embodied commercially in various assemblies. Indeed, there are guiding devices with a longitudinal rib having a small cross section, guiding devices with a rib having a larger cross section, devices with two ribs, etc. Each corresponding sole assembly has one or more grooves adapted to receive the rib(s). Therefore, there are boots whose sole assembly has a groove having a small cross section, a groove having a larger cross section, two grooves, etc.
In any case, an outer sole assembly is adapted to cooperate with a particular guiding device, i.e., exclusive of any other. Thus, the recessed shape of the outer sole assembly is the counterpart of the embossed shape of the associated guiding device. This optimizes the cooperation between the outer sole assembly and the device, for a more precise control of the ski. It is therefore not possible for a user to retain his/her boots when changing to a new guiding device, unless the guiding device has a structure that is adaptable to the structure of the boot. Changing a guiding device, therefore, is often correlated with changing the device retaining the boot to the ski. Indeed, the two types of devices are very often paired with another for various reasons, such as simplifying their manufacture, matching their aesthetic appearance, or similar reasons. The user may wish to change his/her retaining devices, or skis, which can be provided with retaining and guiding devices. However, the user is generally not very inclined to change his/her boots, because the various models do not offer exactly the same sensations of comfort or of foot support. Therefore, a problem arises if the user is not able to keep his/her boots when changing the guiding devices, the retaining devices, or the skis.